초록
It is necessary to improve mechanical and optical properties in the optical disk substrates as the information storage density using short wavelength laser are being developed. The birefringence distribution is regarded as one of the most important optical properties for optical disk. In the present study, the birefringence distrubution is calculated using the Leonov model for viscoelastic constitutive equations and Cross/WLF model for viscosity approximation. The effects of processing conditions upon the development of birefringence discosity approximation. The effects of processing conditions upon the development of birefringence distribution in the optical disk were examined theoretically. It was found that the values of the birefringence distributions were very sensitive to the mold wall temperature history which minimizes the birefringence distribution. The analytical results showed the possibility of improving mechanical and optical properties in the optical disk substrates by active control of the mold wall temperature history.